// Shows how the WBL / getLastError logic depends on the actual chunks which are moved
// We should probably either always wait for writebacks, or don't at all

var st = new ShardingTest({ shards : 2, mongos : 2, verbose : 2, other : { separateConfig : true } })

jsTest.log( "Doing test setup..." )

// Stop balancer, since it'll just get in the way of this
st.stopBalancer()

var mongos = st.s
var admin = mongos.getDB("admin")
var config = mongos.getDB("config")
var coll = st.s.getCollection( jsTest.name() + ".coll" )

st.shardColl( coll, { _id : 1 }, { _id : 0 }, false )

jsTest.log( "Refreshing second mongos..." )

var mongosB = st.s1
var adminB = mongosB.getDB("admin")
var collB = mongosB.getCollection( coll + "" )

// Make sure mongosB knows about the coll
assert.eq( 0, collB.find().itcount() )
// printjson( adminB.runCommand({ flushRouterConfig : 1 }) )

jsTest.log( "Moving chunk to create stale mongos..." )

var otherShard = config.chunks.findOne({ _id : sh._collRE( coll ) }).shard
for( var i = 0; i < st._shardNames.length; i++ ){
    if( otherShard != st._shardNames[i] ){
        otherShard = st._shardNames[i]
        break
    }
}

print( "Other shard : " + otherShard )

printjson( admin.runCommand({ moveChunk : coll + "", find : { _id : 0 }, to : otherShard }) )

jsTest.log( "Inserting docs to be written back..." )

var nextId = -1
// Create writebacks, could add more here
for( var i = 0; i < 2; i++ ){
    printjson( "Inserting " + nextId )
    collB.insert({ _id : nextId--, hello : "world" })
}

// Refresh server
printjson( adminB.runCommand({ flushRouterConfig : 1 }) )

jsTest.log( "Inserting doc which successfully goes through..." )

// Do second write
collB.insert({ _id : nextId--, goodbye : "world" })

printjson( collB.getDB().getLastErrorObj() )

// Get error for last write
//assert.eq( null, collB.getDB().getLastError() )

jsTest.log( "GLE waited for the writebacks." )
 
// Assert that we waited for the writebacks...
assert.eq( coll.find().itcount(), 3 )

/*

jsTest.log( "Waiting for the writeback..." )

assert.soon(function(){
    var count = coll.find().itcount()
    print( "Count is : " + count )
    return count == 3
})

*/

jsTest.log( "Now try moving the actual chunk we're writing to..." )

// Now move the actual chunk we're writing to
printjson( admin.runCommand({ moveChunk : coll + "", find : { _id : -1 }, to : otherShard }) )

jsTest.log( "Inserting second docs to get written back..." )

// Will fail entirely if too many of these, gle will wait too long
for( var i = 0; i < 2; i++ ){
    collB.insert({ _id : nextId--, hello : "world" })
}

// Refresh server
printjson( adminB.runCommand({ flushRouterConfig : 1 }) )

jsTest.log( "Inserting second doc which successfully goes through..." )

// Do second write
collB.insert({ _id : nextId--, goodbye : "world" })

jsTest.log( "GLE is now waiting for the writeback!" )

// Get error for last write
assert.eq( null, collB.getDB().getLastError() )

jsTest.log( "All docs written this time!" )

// Assert that we now waited for the writeback
assert.eq( coll.find().itcount(), 6 )

jsTest.log( "DONE" )

st.stop()